Hey guys, I'm looking at getting a 12v 5 speed 96-98 2500 4x4 short bed quad cab, miles dont really matter. What should I look for as far as what goes wrong? Can you tell by looking at it if the KDP has been fixed? I figured the usual checking of mechanical systems like making sure the steering is tight, checking suspension, u joints..........What are common problems that occur with these trucks that I should look for? I need to know all I can to make sure I dont get screwed. Also what should I do to make sure the engine is in good shape, just see how well it was taken care of like new filters, fairly clean air filter, no rust on body...stuff like that? Is there anyway to see how much clutch it has left without pulling a cover or something like that? I doubt they would let me take it home to pull it apart. How should the tranny feel when shifting. How should the 4x4 work? Is there any little noises to listen for in the engine that are tell tale signs that it is gonna die soon? How should one drive like when does the turbo come in and is it press you back in the seat torque, pretty respectable, or are they slow stock. Should they smoke when they start and how hard should it be to start, how long do they crank? Is there anything in the interior that is prone to breaking or wearing out? This is my first cummins and dont want to get something that has a lot of problems that I dont know about.
Thanks,
Mack

 

The rule of thumb on the 12 valve engines is that they run pretty much forever if they are serviced and not abused. I routinely see them with over 400,000 miles and now quite a few with over a million miles, and they are going strong.

Somewhere around 200,000 miles most exhaust valve seats crack, and the head requires replacement if the truck was used in the mountain states or towed heavy loads frequently. So, factor that into your purchase. If the owner did not stay on top of the exhaust manifold gaskets and bolts, they can break and let the manifold leak. That generally requires a new manifold and head, or the exhaust flanges on the existing head machined true again. Frankly, the OEM exhaust manifold should be tossed and replaced with an ATS three piece unit anyway, they perform better and never leak. You can tell by reaching your hand around the manifold when it is cold and first started, you will feel the exhaust pulses if it is leaking around the flanges to the head. Do not fall for the old "just replace the exhaust manifold gasket trick, it only holds for a short time and then leaks worse than ever - just replace everything.

Most 96-98's are pushing close to 200,000 miles by now, so I would recommend you take the truck to a Cummins Service Center and have it given a compression test and evaluated by them. That is not cheap, around $200, but is a lot less expensive than a new head, rebuild, or turbo. If it checks out and you want it, have Cummins replace the fuel heater. All the OEM versions leak air around the electrical connection sooner or later, so just beat the rush and replace it when they have it in the shop. Use a genuine Cummins Service Center, not Joe's truck and toothbrush repair, you want a real Cummins mechanic to look it over for you.

If you have a good diesel performance shop in your area, most of them can do a decent evaluation. But, first make sure that diesels is all they do.

There is no way to easily tell if the dowel pin has been fixed unless someone used the jig and bolt trick to hold it it. If that was done, you will see a hole drilled through the front gearcase cover with a bolt stuck in the thing. It will be to the inside of the engine oil filler, near the engine centerline, and right through the sheet metal cover. Most shops now will paint a fix date and note on the front gearcase cover, but for years most did not.

If the old upper dowel fell out and broke the aluminum gearcase, that is not always easy to see, and some slick guys try and conceal the damage and then dump their trucks. Look closely with a mirror and really bright light all along the housing where it abuts the fan bearing. Look for oil leakage back in the joint where the gearcase joins the block, right beside the fan bearing, if there is any walk away! If the area is dirty and greasy, walk away!

Go to www.dodgeram.org and look over the TSR's and you will see the usual compliment of body leaks, things falling off, and window and door seal problems. That is pretty much the case with all domestic trucks, so Dodge is not much worse than the competition in the body area. Just the usual welds that some moron forgot to weld, door seals that leak, and the like.

For the front end of a 4X4, hop under the truck with a big pry bar and pipe wrench, and really put the twist on the locating link (track bar) that runs from the axle to the frame on the driver's side, all the OEM style fail pretty frequently. The best replacement is from a place in Arizona, and it has steel ends that can be repaired. The other things to check are the usual joints and mounts, but pay particular attention to the spring towers and where they mount to the frame. The 3500's, and 2500's used for pulling stock trailers, are particularly famous for the frame breaking loose from the spring towers, and it is a recall item that generally is not done unless the owner screams like a stuck pig.

Regarding smoke, yes they will smoke when cold. The rule of thumb is white smoke when cold is ok, blue smoke when warm is bad. Black smoke is excessive fuel and usually means the turbo or air pressure system is leaking. That takes a bit of kid's bubble blowing soap and a lot of time to check, but do it. Also check the intercooler for pin holes, particularly if the rig was from a humid climate.

A diesel in good shape, should perform very well stock. However, most of the second generation 12 valves suffer from bad injection pump timing due to a nut on the injector shaft that was left too loose by Cummins. This results in higher than normal EGT's, low power, hard starting, and in an automatic can create all sorts of shifting problems because the throttle linkage then requires too much travel for the OEM throttle position sensor. If you go with an automatic, figure on ordering a resistor for the TPS circuit once you have it timed up where it makes the best power and fuel mileage. Then the linkage does not move far enough to work the sensor.

A 12 valve Cummins in good shape will start right up. The starting cycle depends on the outside temperature, and letting the heaters cycle enough to warm the intake air.

Lastly, if you buy the truck figure on pulling the oil pan and tossing the plastic piston oiler nozzles. Replace them with steel units. The job sounds worse than it is, just pick up a Haynes Manual #30041, and it will show you what is involved. The plastic nozzles fall out if you run the engine hard and let the oil get very warm, so replacement is a preventative maintenance issue more than anything else.

Good luck.

 

They are great trucks and if you get one that has been taken care of, they will last for ever. Just a technical note - I don't think they started making the short bed quad cab's until 98, and Dodge phased in the 24 valve engine 1/2 way through 98, so if its a 12 valve SB QC you want, 98 to 98.5 is what you want to look for. They are rare, but every now and then you see one.

Good luck with your hunt!

-Vic